package org.geometerplus.fbreader.fbreader;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PointF;
import android.graphics.Region;
import android.graphics.drawable.GradientDrawable;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View;

public class FBReaderView  extends View{


	private static final String TAG = "FBReaderView";
	private static final boolean DEBUG = true;
	
	
	private FBReaderApp myReader;
	
	 private int mWidth = 480;
	 private int mHeight = 800;
	 private int mCornerX = 0; //拖拽点对应的页脚
	 private int mCornerY = 0;
	 private Path mPath0;
	 private Path mPath1;
	 Bitmap mCurPageBitmap = null; //当前页
	 Bitmap mCurPageBackBitmap = null;
	 Bitmap mNextPageBitmap = null;

	 PointF mTouch = new PointF(); // 拖拽点
	 PointF mBezierStart1 = new PointF(); //贝塞尔曲线起始点
	 PointF mBezierControl1 = new PointF(); //贝塞尔曲线控制点
	 PointF mBeziervertex1 = new PointF(); //贝塞尔曲线顶点
	 PointF mBezierEnd1 = new PointF(); //贝塞尔曲线结束点

	 PointF mBezierStart2 = new PointF(); //另一条贝塞尔曲线
	 PointF mBezierControl2 = new PointF();
	 PointF mBeziervertex2 = new PointF();
	 PointF mBezierEnd2 = new PointF();

	 float mMiddleX;
	 float mMiddleY;
	 float mDegrees;
	 float mTouchToCornerDis;
	 ColorMatrixColorFilter mColorMatrixFilter;
	 Matrix mMatrix;
	 float[] mMatrixArray = { 0, 0, 0, 0, 0, 0, 0, 0, 1.0f };

	 boolean mIsRTandLB; //是否属于右上左下
	 float mMaxLength = (float) Math.hypot(480, 800);
	 int[] mBackShadowColors;
	 int[] mFrontShadowColors;
	 GradientDrawable mBackShadowDrawableLR;
	 GradientDrawable mBackShadowDrawableRL;
	 GradientDrawable mFolderShadowDrawableLR;
	 GradientDrawable mFolderShadowDrawableRL;

	 GradientDrawable mFrontShadowDrawableHBT;
	 GradientDrawable mFrontShadowDrawableHTB;
	 GradientDrawable mFrontShadowDrawableVLR;
	 GradientDrawable mFrontShadowDrawableVRL;

	 private Bitmap mBitmap;
	 private Canvas mCanvas;
	 private Paint mBitmapPaint;
	 Paint paint;

	 Paint mPaint;

	 public FBReaderView(Context context) {
	  super(context);
	  // TODO Auto-generated constructor stub
	  mPath0 = new Path();
	  mPath1 = new Path();
	  createDrawable();

	  mBitmap = Bitmap.createBitmap(480, 800, Bitmap.Config.ARGB_8888);

	  mCanvas = new Canvas(mBitmap);
	  mBitmapPaint = new Paint(Paint.DITHER_FLAG);

	  paint = new Paint();
	  mPaint = new Paint();
	  mPaint.setStyle(Paint.Style.FILL);

	 /* mCurPageBitmap = BitmapFactory.decodeResource(this.getResources(),
	    R.drawable.page1);
	  mNextPageBitmap = BitmapFactory.decodeResource(this.getResources(),
	    R.drawable.page2);*/

	  ColorMatrix cm = new ColorMatrix();
	  float array[] = { 0.55f, 0, 0, 0, 80.0f, 0, 0.55f, 0, 0, 80.0f, 0, 0,
	    0.55f, 0, 80.0f, 0, 0, 0, 0.2f, 0 };
	  cm.set(array);
	  mColorMatrixFilter = new ColorMatrixColorFilter(cm);

	  mMatrix = new Matrix();
	 }

	 /**
	  * 计算拖拽点对应的拖拽脚
	  */
	 private void calcCornerXY(float x, float y) {
	  if (x <= mWidth / 2)
	   mCornerX = 0;
	  else
	   mCornerX = mWidth;
	  if (y <= mHeight / 2)
	   mCornerY = 0;
	  else
	   mCornerY = mHeight;
	  if ((mCornerX == 0 && mCornerY == mHeight)
	    || (mCornerX == mWidth && mCornerY == 0))
	   mIsRTandLB = true;
	  else
	   mIsRTandLB = false;
	 }

	 @Override
	 public boolean onTouchEvent(MotionEvent event) {
	  // TODO Auto-generated method stub
	  if (event.getAction() == MotionEvent.ACTION_MOVE) {//手指移动
	   mCanvas.drawColor(0xFFAAAAAA);
	   mTouch.x = event.getX();
	   mTouch.y = event.getY();
	   this.postInvalidate();//更新视图
	  }
	  if (event.getAction() == MotionEvent.ACTION_DOWN) {//手指按下
	   mCanvas.drawColor(0xFFAAAAAA);
	   mTouch.x = event.getX();
	   mTouch.y = event.getY();
	   calcCornerXY(mTouch.x, mTouch.y);
	   this.postInvalidate();
	  }
	  if (event.getAction() == MotionEvent.ACTION_UP) {//手指松开
	   mCanvas.drawColor(0xFFAAAAAA);
	   mTouch.x = mCornerX;
	   mTouch.y = mCornerY;
	   this.postInvalidate();
	  }
	  return true;
	 }

	 /**
	  * 求解直线P1P2和直线P3P4的交点坐标
	  */
	 public PointF getCross(PointF P1, PointF P2, PointF P3, PointF P4) {
	  PointF CrossP = new PointF();
	  // 二元函数通式： y=ax+b
	  float a1 = (P2.y - P1.y) / (P2.x - P1.x);
	  float b1 = ((P1.x * P2.y) - (P2.x * P1.y)) / (P1.x - P2.x);

	  float a2 = (P4.y - P3.y) / (P4.x - P3.x);
	  float b2 = ((P3.x * P4.y) - (P4.x * P3.y)) / (P3.x - P4.x);
	  CrossP.x = (b2 - b1) / (a1 - a2);
	  CrossP.y = a1 * CrossP.x + b1;
	  return CrossP;
	 }

	 private void calcPoints() {
	  mMiddleX = (mTouch.x + mCornerX) / 2;
	  mMiddleY = (mTouch.y + mCornerY) / 2;
	  mBezierControl1.x = mMiddleX - (mCornerY - mMiddleY)
	    * (mCornerY - mMiddleY) / (mCornerX - mMiddleX);
	  mBezierControl1.y = mCornerY;
	  mBezierControl2.x = mCornerX;
	  mBezierControl2.y = mMiddleY - (mCornerX - mMiddleX)
	    * (mCornerX - mMiddleX) / (mCornerY - mMiddleY);

	  Log.i(TAG, "mTouchX  " + mTouch.x + "  mTouchY  " + mTouch.y);
	  Log.i(TAG, "mBezierControl1.x  " + mBezierControl1.x
	    + "  mBezierControl1.y  " + mBezierControl1.y);
	  Log.i(TAG, "mBezierControl2.x  " + mBezierControl2.x
	    + "  mBezierControl2.y  " + mBezierControl2.y);

	  mBezierStart1.x = mBezierControl1.x - (mCornerX - mBezierControl1.x)
	    / 2;
	  mBezierStart1.y = mCornerY;

	  // 当mBezierStart1.x < 0或者mBezierStart1.x > 480时
	  // 如果继续翻页，会出现BUG故在此限制
	  if (mBezierStart1.x < 0 || mBezierStart1.x > 480) {   
	   if (mBezierStart1.x < 0)         
	    mBezierStart1.x = mWidth - mBezierStart1.x;

	   float f1 = Math.abs(mCornerX - mTouch.x);
	   float f2 = mWidth * f1 / mBezierStart1.x;
	   mTouch.x = Math.abs(mCornerX - f2);

	   float f3 = Math.abs(mCornerX - mTouch.x)
	     * Math.abs(mCornerY - mTouch.y) / f1;
	   mTouch.y = Math.abs(mCornerY - f3);
	   mMiddleX = (mTouch.x + mCornerX) / 2;
	   mMiddleY = (mTouch.y + mCornerY) / 2;

	   mBezierControl1.x = mMiddleX - (mCornerY - mMiddleY)
	     * (mCornerY - mMiddleY) / (mCornerX - mMiddleX);
	   mBezierControl1.y = mCornerY;

	   mBezierControl2.x = mCornerX;
	   mBezierControl2.y = mMiddleY - (mCornerX - mMiddleX)
	     * (mCornerX - mMiddleX) / (mCornerY - mMiddleY);
	   Log.i(TAG, "mTouchX --> " + mTouch.x + "  mTouchY-->  "
	     + mTouch.y);
	   Log.i(TAG, "mBezierControl1.x--  " + mBezierControl1.x
	     + "  mBezierControl1.y -- " + mBezierControl1.y);
	   Log.i(TAG, "mBezierControl2.x -- " + mBezierControl2.x
	     + "  mBezierControl2.y -- " + mBezierControl2.y);
	   mBezierStart1.x = mBezierControl1.x
	     - (mCornerX - mBezierControl1.x) / 2;
	  }

	  mBezierStart2.x = mCornerX;
	  mBezierStart2.y = mBezierControl2.y - (mCornerY - mBezierControl2.y)
	    / 2;

	  mTouchToCornerDis = (float) Math.hypot((mTouch.x - mCornerX),
	    (mTouch.y - mCornerY));

	  mBezierEnd1 = getCross(mTouch, mBezierControl1, mBezierStart1,
	    mBezierStart2);
	  mBezierEnd2 = getCross(mTouch, mBezierControl2, mBezierStart1,
	    mBezierStart2);

	  Log.i(TAG, "mBezierEnd1.x  " + mBezierEnd1.x + "  mBezierEnd1.y  "
	    + mBezierEnd1.y);
	  Log.i(TAG, "mBezierEnd2.x  " + mBezierEnd2.x + "  mBezierEnd2.y  "
	    + mBezierEnd2.y);

	  /*
	   * mBeziervertex1.x 推导
	   * ((mBezierStart1.x+mBezierEnd1.x)/2+mBezierControl1.x)/2 化简等价于
	   * (mBezierStart1.x+ 2*mBezierControl1.x+mBezierEnd1.x) / 4
	   */
	  mBeziervertex1.x = (mBezierStart1.x + 2 * mBezierControl1.x + mBezierEnd1.x) / 4;
	  mBeziervertex1.y = (2 * mBezierControl1.y + mBezierStart1.y + mBezierEnd1.y) / 4;
	  mBeziervertex2.x = (mBezierStart2.x + 2 * mBezierControl2.x + mBezierEnd2.x) / 4;
	  mBeziervertex2.y = (2 * mBezierControl2.y + mBezierStart2.y + mBezierEnd2.y) / 4;
	 }

	 private void drawCurrentPageArea(Canvas canvas, Bitmap bitmap, Path path) {
	  mPath0.reset();
	  mPath0.moveTo(mBezierStart1.x, mBezierStart1.y);
	  mPath0.quadTo(mBezierControl1.x, mBezierControl1.y, mBezierEnd1.x,
	    mBezierEnd1.y);
	  mPath0.lineTo(mTouch.x, mTouch.y);
	  mPath0.lineTo(mBezierEnd2.x, mBezierEnd2.y);
	  mPath0.quadTo(mBezierControl2.x, mBezierControl2.y, mBezierStart2.x,
	    mBezierStart2.y);
	  mPath0.lineTo(mCornerX, mCornerY);
	  mPath0.close();

	  canvas.save();
	  canvas.clipPath(path, Region.Op.XOR);
	  canvas.drawBitmap(bitmap, 0, 0, null);
	  canvas.restore();
	 }

	 private void drawNextPageAreaAndShadow(Canvas canvas, Bitmap bitmap) {
	  mPath1.reset();
	  mPath1.moveTo(mBezierStart1.x, mBezierStart1.y);
	  mPath1.lineTo(mBeziervertex1.x, mBeziervertex1.y);
	  mPath1.lineTo(mBeziervertex2.x, mBeziervertex2.y);
	  mPath1.lineTo(mBezierStart2.x, mBezierStart2.y);
	  mPath1.lineTo(mCornerX, mCornerY);
	  mPath1.close();

	  mDegrees = (float) Math.toDegrees(Math.atan2(mBezierControl1.x
	    - mCornerX, mBezierControl2.y - mCornerY));
	  int leftx;
	  int rightx;
	  GradientDrawable mBackShadowDrawable;
	  if (mIsRTandLB) {
	   leftx = (int) (mBezierStart1.x);
	   rightx = (int) (mBezierStart1.x + mTouchToCornerDis / 4);
	   mBackShadowDrawable = mBackShadowDrawableLR;
	  } else {
	   leftx = (int) (mBezierStart1.x - mTouchToCornerDis / 4);
	   rightx = (int) mBezierStart1.x;
	   mBackShadowDrawable = mBackShadowDrawableRL;
	  }
	  canvas.save();
	  canvas.clipPath(mPath0);
	  canvas.clipPath(mPath1, Region.Op.INTERSECT);
	  canvas.drawBitmap(bitmap, 0, 0, null);
	  canvas.rotate(mDegrees, mBezierStart1.x, mBezierStart1.y);
	  mBackShadowDrawable.setBounds(leftx, (int) mBezierStart1.y, rightx,
	    (int) (mMaxLength + mBezierStart1.y));
	  mBackShadowDrawable.draw(canvas);
	  canvas.restore();
	 }

	 public void setBitmaps(Bitmap bm1, Bitmap bm2, Bitmap bm3) {
	  mCurPageBitmap = bm1;
	  mCurPageBackBitmap = bm2;
	  mNextPageBitmap = bm3;
	 }

	 @Override
	 protected void onDraw(Canvas canvas) {
	  canvas.drawColor(0xFFAAAAAA);
	  calcPoints();
	  drawCurrentPageArea(mCanvas, mCurPageBitmap, mPath0);
	  drawNextPageAreaAndShadow(mCanvas, mNextPageBitmap);
	  drawCurrentPageShadow(mCanvas);
	  drawCurrentBackArea(mCanvas, mCurPageBitmap);
	  canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
	 }

	 /**
	  *创建阴影的GradientDrawable
	  */
	 private void createDrawable() {
	  int[] color = { 0x333333, 0xb0333333 };
	  mFolderShadowDrawableRL = new GradientDrawable(
	    GradientDrawable.Orientation.RIGHT_LEFT, color);
	  mFolderShadowDrawableRL
	    .setGradientType(GradientDrawable.LINEAR_GRADIENT);

	  mFolderShadowDrawableLR = new GradientDrawable(
	    GradientDrawable.Orientation.LEFT_RIGHT, color);
	  mFolderShadowDrawableLR
	    .setGradientType(GradientDrawable.LINEAR_GRADIENT);

	  mBackShadowColors = new int[] { 0xff111111, 0x111111 };
	  mBackShadowDrawableRL = new GradientDrawable(
	    GradientDrawable.Orientation.RIGHT_LEFT, mBackShadowColors);
	  mBackShadowDrawableRL.setGradientType(GradientDrawable.LINEAR_GRADIENT);

	  mBackShadowDrawableLR = new GradientDrawable(
	    GradientDrawable.Orientation.LEFT_RIGHT, mBackShadowColors);
	  mBackShadowDrawableLR.setGradientType(GradientDrawable.LINEAR_GRADIENT);

	  mFrontShadowColors = new int[] { 0x80111111, 0x111111 };
	  mFrontShadowDrawableVLR = new GradientDrawable(
	    GradientDrawable.Orientation.LEFT_RIGHT, mFrontShadowColors);
	  mFrontShadowDrawableVLR
	    .setGradientType(GradientDrawable.LINEAR_GRADIENT);
	  mFrontShadowDrawableVRL = new GradientDrawable(
	    GradientDrawable.Orientation.RIGHT_LEFT, mFrontShadowColors);
	  mFrontShadowDrawableVRL
	    .setGradientType(GradientDrawable.LINEAR_GRADIENT);

	  mFrontShadowDrawableHTB = new GradientDrawable(
	    GradientDrawable.Orientation.TOP_BOTTOM, mFrontShadowColors);
	  mFrontShadowDrawableHTB
	    .setGradientType(GradientDrawable.LINEAR_GRADIENT);

	  mFrontShadowDrawableHBT = new GradientDrawable(
	    GradientDrawable.Orientation.BOTTOM_TOP, mFrontShadowColors);
	  mFrontShadowDrawableHBT
	    .setGradientType(GradientDrawable.LINEAR_GRADIENT);
	 }

	 /**
	  * 绘制翻起页的阴影
	  */
	 public void drawCurrentPageShadow(Canvas canvas) {
	  double degree;
	  if (mIsRTandLB) {
	   degree = Math.PI
	     / 4
	     - Math.atan2(mBezierControl1.y - mTouch.y, mTouch.x
	       - mBezierControl1.x);
	  } else {
	   degree = Math.PI
	     / 4
	     - Math.atan2(mTouch.y - mBezierControl1.y, mTouch.x
	       - mBezierControl1.x);
	  }
	  //翻起页阴影顶点与touch点的距离
	  double d1 = (float) 25 * 1.414 * Math.cos(degree);
	  double d2 = (float) 25 * 1.414 * Math.sin(degree);
	  float x = (float) (mTouch.x + d1);
	  float y;
	  if (mIsRTandLB) {
	   y = (float) (mTouch.y + d2);   
	  } else {
	   y = (float) (mTouch.y - d2);
	  }
	  mPath1.reset();
	  mPath1.moveTo(x, y);
	  mPath1.lineTo(mTouch.x, mTouch.y);
	  mPath1.lineTo(mBezierControl1.x, mBezierControl1.y);
	  mPath1.lineTo(mBezierStart1.x, mBezierStart1.y);
	  mPath1.close();
	  float rotateDegrees;
	  canvas.save();

	  canvas.clipPath(mPath0, Region.Op.XOR);
	  canvas.clipPath(mPath1, Region.Op.INTERSECT);
	  int leftx;
	  int rightx;
	  GradientDrawable mCurrentPageShadow;
	  if (mIsRTandLB) {
	   leftx = (int) (mBezierControl1.x);
	   rightx = (int) mBezierControl1.x + 25;
	   mCurrentPageShadow = mFrontShadowDrawableVLR;
	  } else {
	   leftx = (int) (mBezierControl1.x - 25);
	   rightx = (int) mBezierControl1.x + 1;
	   mCurrentPageShadow = mFrontShadowDrawableVRL;
	  }

	  rotateDegrees = (float) Math.toDegrees(Math.atan2(mTouch.x
	    - mBezierControl1.x, mBezierControl1.y - mTouch.y));
	  canvas.rotate(rotateDegrees, mBezierControl1.x, mBezierControl1.y);
	  mCurrentPageShadow.setBounds(leftx,
	    (int) (mBezierControl1.y - mMaxLength), rightx,
	    (int) (mBezierControl1.y));
	  mCurrentPageShadow.draw(canvas);
	  canvas.restore();

	  mPath1.reset();
	  mPath1.moveTo(x, y);
	  mPath1.lineTo(mTouch.x, mTouch.y);
	  mPath1.lineTo(mBezierControl2.x, mBezierControl2.y);
	  mPath1.lineTo(mBezierStart2.x, mBezierStart2.y);
	  mPath1.close();
	  canvas.save();
	  canvas.clipPath(mPath0, Region.Op.XOR);
	  canvas.clipPath(mPath1, Region.Op.INTERSECT);
	  if (mIsRTandLB) {
	   leftx = (int) (mBezierControl2.y);
	   rightx = (int) (mBezierControl2.y + 25);
	   mCurrentPageShadow = mFrontShadowDrawableHTB;
	  } else {
	   leftx = (int) (mBezierControl2.y - 25);
	   rightx = (int) (mBezierControl2.y + 1);
	   mCurrentPageShadow = mFrontShadowDrawableHBT;
	  }
	  rotateDegrees = (float) Math.toDegrees(Math.atan2(mBezierControl2.y
	    - mTouch.y, mBezierControl2.x - mTouch.x));
	  canvas.rotate(rotateDegrees, mBezierControl2.x, mBezierControl2.y);
	  float temp;
	  if (mBezierControl2.y < 0)
	   temp = mBezierControl2.y - 800;
	  else
	   temp = mBezierControl2.y;

	  int hmg = (int) Math.hypot(mBezierControl2.x, temp);
	  if (hmg > mMaxLength)
	   mCurrentPageShadow
	     .setBounds((int) (mBezierControl2.x - 25) - hmg, leftx,
	       (int) (mBezierControl2.x + mMaxLength) - hmg,
	       rightx);
	  else
	   mCurrentPageShadow.setBounds(
	     (int) (mBezierControl2.x - mMaxLength), leftx,
	     (int) (mBezierControl2.x), rightx);

	  Log.i(TAG, "mBezierControl2.x   " + mBezierControl2.x
	    + "  mBezierControl2.y  " + mBezierControl2.y);
	  mCurrentPageShadow.draw(canvas);
	  canvas.restore();
	 }

	 /**
	  *  绘制翻起页背面
	  */
	 private void drawCurrentBackArea(Canvas canvas, Bitmap bitmap) {
	  int i = (int) (mBezierStart1.x + mBezierControl1.x) / 2;
	  float f1 = Math.abs(i - mBezierControl1.x);
	  int i1 = (int) (mBezierStart2.y + mBezierControl2.y) / 2;
	  float f2 = Math.abs(i1 - mBezierControl2.y);
	  float f3 = Math.min(f1, f2);
	  mPath1.reset();
	  mPath1.moveTo(mBeziervertex2.x, mBeziervertex2.y);
	  mPath1.lineTo(mBeziervertex1.x, mBeziervertex1.y);
	  mPath1.lineTo(mBezierEnd1.x, mBezierEnd1.y);
	  mPath1.lineTo(mTouch.x, mTouch.y);
	  mPath1.lineTo(mBezierEnd2.x, mBezierEnd2.y);
	  mPath1.close();
	  GradientDrawable mFolderShadowDrawable;
	  int left;
	  int right;
	  if (mIsRTandLB) {
	   left = (int) (mBezierStart1.x - 1);
	   right = (int) (mBezierStart1.x + f3 + 1);
	   mFolderShadowDrawable = mFolderShadowDrawableLR;
	  } else {
	   left= (int) (mBezierStart1.x - f3 - 1);
	   right= (int) (mBezierStart1.x + 1);
	   mFolderShadowDrawable = mFolderShadowDrawableRL;
	  }
	  canvas.save();
	  canvas.clipPath(mPath0);
	  canvas.clipPath(mPath1, Region.Op.INTERSECT);

	  mPaint.setColorFilter(mColorMatrixFilter);

	  float dis = (float) Math.hypot(mCornerX - mBezierControl1.x,
	    mBezierControl2.y - mCornerY);
	  float f8 = (mCornerX - mBezierControl1.x) / dis;
	  float f9 = (mBezierControl2.y - mCornerY) / dis;
	  mMatrixArray[0] = 1 - 2 * f9 * f9;
	  mMatrixArray[1] = 2 * f8 * f9;
	  mMatrixArray[3] = mMatrixArray[1];
	  mMatrixArray[4] = 1 - 2 * f8 * f8;
	  mMatrix.reset();
	  mMatrix.setValues(mMatrixArray);
	  mMatrix.preTranslate(-mBezierControl1.x, -mBezierControl1.y);
	  mMatrix.postTranslate(mBezierControl1.x, mBezierControl1.y);
	  canvas.drawBitmap(bitmap, mMatrix, mPaint);
	  mPaint.setColorFilter(null);
	  canvas.rotate(mDegrees, mBezierStart1.x, mBezierStart1.y);
	  mFolderShadowDrawable.setBounds(left, (int) mBezierStart1.y, right,
	    (int) (mBezierStart1.y + mMaxLength));
	  mFolderShadowDrawable.draw(canvas);
	  canvas.restore();
	 }
	}

